/*
 * #%L
 * HAPI FHIR JPA Model
 * %%
 * Copyright (C) 2014 - 2025 Smile CDR, Inc.
 * %%
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * #L%
 */
package ca.uhn.fhir.jpa.model.entity;

import ca.uhn.fhir.jpa.model.dao.JpaPid;
import jakarta.persistence.Column;
import jakarta.persistence.Entity;
import jakarta.persistence.FetchType;
import jakarta.persistence.ForeignKey;
import jakarta.persistence.GeneratedValue;
import jakarta.persistence.GenerationType;
import jakarta.persistence.Id;
import jakarta.persistence.IdClass;
import jakarta.persistence.Index;
import jakarta.persistence.JoinColumn;
import jakarta.persistence.JoinColumns;
import jakarta.persistence.ManyToOne;
import jakarta.persistence.PostLoad;
import jakarta.persistence.Table;
import jakarta.persistence.Temporal;
import jakarta.persistence.TemporalType;
import jakarta.persistence.Transient;
import org.apache.commons.lang3.Validate;
import org.apache.commons.lang3.builder.EqualsBuilder;
import org.apache.commons.lang3.builder.HashCodeBuilder;
import org.hibernate.annotations.GenericGenerator;
import org.hibernate.search.mapper.pojo.mapping.definition.annotation.FullTextField;
import org.hl7.fhir.instance.model.api.IIdType;

import java.time.LocalDate;
import java.util.Date;

@Entity
@Table(
                name = "HFJ_RES_LINK",
                indexes = {
                        // We need to join both ways, so index from src->tgt and from tgt->src.
                        // From src->tgt, rows are usually written all together as part of ingestion - keep the index small, and
                        // read blocks as needed.
                        @Index(name = "IDX_RL_SRC", columnList = "SRC_RESOURCE_ID"),
                        // But from tgt->src, include all the match columns. Targets will usually be randomly distributed - each row
                        // in separate block.
                        @Index(
                                        name = "IDX_RL_TGT_v2",
                                        columnList = "TARGET_RESOURCE_ID, SRC_PATH, SRC_RESOURCE_ID, TARGET_RESOURCE_TYPE,PARTITION_ID")
                })
@IdClass(IdAndPartitionId.class)
public class ResourceLink extends BaseResourceIndex {

        public static final int SRC_PATH_LENGTH = 500;
        private static final long serialVersionUID = 1L;
        public static final String TARGET_RES_PARTITION_ID = "TARGET_RES_PARTITION_ID";
        public static final String TARGET_RESOURCE_ID = "TARGET_RESOURCE_ID";
        public static final String FK_RESLINK_TARGET = "FK_RESLINK_TARGET";

        @GenericGenerator(name = "SEQ_RESLINK_ID", type = ca.uhn.fhir.jpa.model.dialect.HapiSequenceStyleGenerator.class)
        @GeneratedValue(strategy = GenerationType.AUTO, generator = "SEQ_RESLINK_ID")
        @Id
        @Column(name = "PID")
        private Long myId;

        @Column(name = "SRC_PATH", length = SRC_PATH_LENGTH, nullable = false)
        private String mySourcePath;

        @ManyToOne(
                        optional = false,
                        fetch = FetchType.LAZY,
                        cascade = {})
        @JoinColumns(
                        value = {
                                @JoinColumn(
                                                name = "SRC_RESOURCE_ID",
                                                referencedColumnName = "RES_ID",
                                                insertable = false,
                                                updatable = false,
                                                nullable = false),
                                @JoinColumn(
                                                name = "PARTITION_ID",
                                                referencedColumnName = "PARTITION_ID",
                                                insertable = false,
                                                updatable = false,
                                                nullable = false)
                        },
                        foreignKey = @ForeignKey(name = "FK_RESLINK_SOURCE"))
        private ResourceTable mySourceResource;

        @Column(name = "SRC_RESOURCE_ID", nullable = false)
        private Long mySourceResourcePid;

        @Column(name = "SOURCE_RESOURCE_TYPE", updatable = false, nullable = false, length = ResourceTable.RESTYPE_LEN)
        @FullTextField
        private String mySourceResourceType;

        @ManyToOne(optional = true, fetch = FetchType.EAGER)
        @JoinColumns(
                        value = {
                                @JoinColumn(
                                                name = TARGET_RESOURCE_ID,
                                                referencedColumnName = "RES_ID",
                                                nullable = true,
                                                insertable = false,
                                                updatable = false),
                                @JoinColumn(
                                                name = TARGET_RES_PARTITION_ID,
                                                referencedColumnName = "PARTITION_ID",
                                                nullable = true,
                                                insertable = false,
                                                updatable = false),
                        },
                        /*
                         * TODO: We need to drop this constraint because it affects performance in pretty
                         *  terrible ways on a lot of platforms. But a Hibernate bug present in Hibernate 6.6.4
                         *  makes it impossible.
                         *  See: https://hibernate.atlassian.net/browse/HHH-19046
                         */
                        foreignKey = @ForeignKey(name = FK_RESLINK_TARGET))
        private ResourceTable myTargetResource;

        @Transient
        private ResourceTable myTransientTargetResource;

        @Column(name = TARGET_RESOURCE_ID, insertable = true, updatable = true, nullable = true)
        @FullTextField
        private Long myTargetResourcePid;

        @Column(name = "TARGET_RESOURCE_TYPE", nullable = false, length = ResourceTable.RESTYPE_LEN)
        @FullTextField
        private String myTargetResourceType;

        @Column(name = "TARGET_RESOURCE_URL", length = 200, nullable = true)
        @FullTextField
        private String myTargetResourceUrl;

        @Column(name = "TARGET_RESOURCE_VERSION", nullable = true)
        private Long myTargetResourceVersion;

        @FullTextField
        @Column(name = "SP_UPDATED", nullable = true) // TODO: make this false after HAPI 2.3
        @Temporal(TemporalType.TIMESTAMP)
        private Date myUpdated;

        @Transient
        private transient String myTargetResourceId;

        @Column(name = TARGET_RES_PARTITION_ID, nullable = true)
        private Integer myTargetResourcePartitionId;

        @Column(name = "TARGET_RES_PARTITION_DATE", nullable = true)
        private LocalDate myTargetResourcePartitionDate;

        /**
         * Constructor
         */
        public ResourceLink() {
                super();
        }

        public Long getTargetResourceVersion() {
                return myTargetResourceVersion;
        }

        public void setTargetResourceVersion(Long theTargetResourceVersion) {
                myTargetResourceVersion = theTargetResourceVersion;
        }

        public String getTargetResourceId() {
                if (myTargetResourceId == null && getTargetResource() != null) {
                        myTargetResourceId = getTargetResource().getIdDt().getIdPart();
                }
                return myTargetResourceId;
        }

        public String getSourceResourceType() {
                return mySourceResourceType;
        }

        public String getTargetResourceType() {
                return myTargetResourceType;
        }

        @Override
        public boolean equals(Object theObj) {
                if (this == theObj) {
                        return true;
                }
                if (theObj == null) {
                        return false;
                }
                if (!(theObj instanceof ResourceLink)) {
                        return false;
                }
                ResourceLink obj = (ResourceLink) theObj;
                EqualsBuilder b = new EqualsBuilder();
                b.append(mySourcePath, obj.mySourcePath);
                b.append(mySourceResource, obj.mySourceResource);
                b.append(myTargetResourceUrl, obj.myTargetResourceUrl);
                b.append(myTargetResourceType, obj.myTargetResourceType);
                b.append(myTargetResourceVersion, obj.myTargetResourceVersion);
                // In cases where we are extracting links from a resource that has not yet been persisted, the target resource
                // pid
                // will be null so we use the target resource id to differentiate instead
                if (getTargetResourcePid() == null) {
                        b.append(getTargetResourceId(), obj.getTargetResourceId());
                } else {
                        b.append(getTargetResourcePid(), obj.getTargetResourcePid());
                }
                return b.isEquals();
        }

        /**
         * ResourceLink.myTargetResource field is immutable.Transient ResourceLink.myTransientTargetResource property
         * is used instead, allowing it to be updated via the ResourceLink#copyMutableValuesFrom method
         * when ResourceLink table row is reused.
         */
        @PostLoad
        public void postLoad() {
                myTransientTargetResource = myTargetResource;
        }

        @Override
        public <T extends BaseResourceIndex> void copyMutableValuesFrom(T theSource) {
                ResourceLink source = (ResourceLink) theSource;
                mySourcePath = source.getSourcePath();
                myTransientTargetResource = source.getTargetResource();
                myTargetResourceId = source.getTargetResourceId();
                myTargetResourcePid = source.getTargetResourcePid();
                myTargetResourceType = source.getTargetResourceType();
                myTargetResourceVersion = source.getTargetResourceVersion();
                myTargetResourceUrl = source.getTargetResourceUrl();
                myTargetResourcePartitionId = source.getTargetResourcePartitionId();
                myTargetResourcePartitionDate = source.getTargetResourcePartitionDate();
        }

        @Override
        public void setResourceId(Long theResourceId) {
                mySourceResourcePid = theResourceId;
        }

        public String getSourcePath() {
                return mySourcePath;
        }

        public void setSourcePath(String theSourcePath) {
                mySourcePath = theSourcePath;
        }

        public JpaPid getSourceResourcePk() {
                return JpaPid.fromId(mySourceResourcePid, myPartitionIdValue);
        }

        public ResourceTable getSourceResource() {
                return mySourceResource;
        }

        public void setSourceResource(ResourceTable theSourceResource) {
                mySourceResource = theSourceResource;
                mySourceResourcePid = theSourceResource.getId().getId();
                mySourceResourceType = theSourceResource.getResourceType();
                setPartitionId(theSourceResource.getPartitionId());
        }

        public void setTargetResource(String theResourceType, Long theResourcePid, String theTargetResourceId) {
                Validate.notBlank(theResourceType);

                myTargetResourceType = theResourceType;
                myTargetResourcePid = theResourcePid;
                myTargetResourceId = theTargetResourceId;
        }

        public String getTargetResourceUrl() {
                return myTargetResourceUrl;
        }

        public void setTargetResourceUrl(IIdType theTargetResourceUrl) {
                Validate.isTrue(theTargetResourceUrl.hasBaseUrl());
                Validate.isTrue(theTargetResourceUrl.hasResourceType());

                //              if (theTargetResourceUrl.hasIdPart()) {
                // do nothing
                //              } else {
                // Must have set an url like http://example.org/something
                // We treat 'something' as the resource type because of fix for #659. Prior to #659 fix, 'something' was
                // treated as the id and 'example.org' was treated as the resource type
                // Maybe log a warning?
                //              }

                myTargetResourceType = theTargetResourceUrl.getResourceType();
                myTargetResourceUrl = theTargetResourceUrl.getValue();
        }

        public Long getTargetResourcePid() {
                return myTargetResourcePid;
        }

        public void setTargetResourceUrlCanonical(String theTargetResourceUrl) {
                Validate.notBlank(theTargetResourceUrl);

                myTargetResourceType = "(unknown)";
                myTargetResourceUrl = theTargetResourceUrl;
        }

        public Date getUpdated() {
                return myUpdated;
        }

        public void setUpdated(Date theUpdated) {
                myUpdated = theUpdated;
        }

        @Override
        public Long getId() {
                return myId;
        }

        @Override
        public void setId(Long theId) {
                myId = theId;
        }

        public LocalDate getTargetResourcePartitionDate() {
                return myTargetResourcePartitionDate;
        }

        public Integer getTargetResourcePartitionId() {
                return myTargetResourcePartitionId;
        }

        public ResourceLink setTargetResourcePartitionId(PartitionablePartitionId theTargetResourcePartitionId) {
                myTargetResourcePartitionId = null;
                myTargetResourcePartitionDate = null;
                if (theTargetResourcePartitionId != null) {
                        myTargetResourcePartitionId = theTargetResourcePartitionId.getPartitionId();
                        myTargetResourcePartitionDate = theTargetResourcePartitionId.getPartitionDate();
                }
                return this;
        }

        @Override
        public void clearHashes() {
                // nothing right now
        }

        @Override
        public void calculateHashes() {
                // nothing right now
        }

        @Override
        public int hashCode() {
                HashCodeBuilder b = new HashCodeBuilder();
                b.append(mySourcePath);
                b.append(mySourceResource);
                b.append(myTargetResourceUrl);
                b.append(myTargetResourceVersion);

                // In cases where we are extracting links from a resource that has not yet been persisted, the target resource
                // pid
                // will be null so we use the target resource id to differentiate instead
                if (getTargetResourcePid() == null) {
                        b.append(getTargetResourceId());
                } else {
                        b.append(getTargetResourcePid());
                }
                return b.toHashCode();
        }

        @Override
        public String toString() {
                StringBuilder b = new StringBuilder();
                b.append("ResourceLink[");
                b.append("path=").append(mySourcePath);
                b.append(", srcResId=").append(mySourceResourcePid);
                b.append(", srcPartition=").append(myPartitionIdValue);
                b.append(", targetResId=").append(myTargetResourcePid);
                b.append(", targetPartition=").append(myTargetResourcePartitionId);
                b.append(", targetResType=").append(myTargetResourceType);
                b.append(", targetResVersion=").append(myTargetResourceVersion);
                b.append(", targetResUrl=").append(myTargetResourceUrl);

                b.append("]");
                return b.toString();
        }

        public ResourceTable getTargetResource() {
                return myTransientTargetResource;
        }

        /**
         * Creates a clone of this resourcelink which doesn't contain the internal PID
         * of the target resource.
         */
        public ResourceLink cloneWithoutTargetPid() {
                ResourceLink retVal = new ResourceLink();
                retVal.mySourceResource = mySourceResource;
                retVal.mySourceResourcePid = mySourceResource.getId().getId();
                retVal.mySourceResourceType = mySourceResource.getResourceType();
                retVal.myPartitionIdValue = mySourceResource.getPartitionId().getPartitionId();
                retVal.mySourcePath = mySourcePath;
                retVal.myUpdated = myUpdated;
                retVal.myTargetResourceType = myTargetResourceType;
                if (myTargetResourceId != null) {
                        retVal.myTargetResourceId = myTargetResourceId;
                } else if (getTargetResource() != null) {
                        retVal.myTargetResourceId = getTargetResource().getIdDt().getIdPart();
                }
                retVal.myTargetResourceUrl = myTargetResourceUrl;
                retVal.myTargetResourceVersion = myTargetResourceVersion;
                return retVal;
        }

        public static ResourceLink forAbsoluteReference(
                        String theSourcePath, ResourceTable theSourceResource, IIdType theTargetResourceUrl, Date theUpdated) {
                ResourceLink retVal = new ResourceLink();
                retVal.setSourcePath(theSourcePath);
                retVal.setSourceResource(theSourceResource);
                retVal.setTargetResourceUrl(theTargetResourceUrl);
                retVal.setUpdated(theUpdated);
                return retVal;
        }

        /**
         * Factory for canonical URL
         */
        public static ResourceLink forLogicalReference(
                        String theSourcePath, ResourceTable theSourceResource, String theTargetResourceUrl, Date theUpdated) {
                ResourceLink retVal = new ResourceLink();
                retVal.setSourcePath(theSourcePath);
                retVal.setSourceResource(theSourceResource);
                retVal.setTargetResourceUrlCanonical(theTargetResourceUrl);
                retVal.setUpdated(theUpdated);
                return retVal;
        }

        public static ResourceLink forLocalReference(
                        ResourceLinkForLocalReferenceParams theResourceLinkForLocalReferenceParams) {

                ResourceLink retVal = new ResourceLink();
                retVal.setSourcePath(theResourceLinkForLocalReferenceParams.getSourcePath());
                retVal.setSourceResource(theResourceLinkForLocalReferenceParams.getSourceResource());
                retVal.setTargetResource(
                                theResourceLinkForLocalReferenceParams.getTargetResourceType(),
                                theResourceLinkForLocalReferenceParams.getTargetResourcePid(),
                                theResourceLinkForLocalReferenceParams.getTargetResourceId());

                retVal.setTargetResourcePartitionId(
                                theResourceLinkForLocalReferenceParams.getTargetResourcePartitionablePartitionId());
                retVal.setTargetResourceVersion(theResourceLinkForLocalReferenceParams.getTargetResourceVersion());
                retVal.setUpdated(theResourceLinkForLocalReferenceParams.getUpdated());

                return retVal;
        }

        public static class ResourceLinkForLocalReferenceParams {
                private String mySourcePath;
                private ResourceTable mySourceResource;
                private String myTargetResourceType;
                private Long myTargetResourcePid;
                private String myTargetResourceId;
                private Date myUpdated;
                private Long myTargetResourceVersion;
                private PartitionablePartitionId myTargetResourcePartitionablePartitionId;

                public static ResourceLinkForLocalReferenceParams instance() {
                        return new ResourceLinkForLocalReferenceParams();
                }

                public String getSourcePath() {
                        return mySourcePath;
                }

                public ResourceLinkForLocalReferenceParams setSourcePath(String theSourcePath) {
                        mySourcePath = theSourcePath;
                        return this;
                }

                public ResourceTable getSourceResource() {
                        return mySourceResource;
                }

                public ResourceLinkForLocalReferenceParams setSourceResource(ResourceTable theSourceResource) {
                        mySourceResource = theSourceResource;
                        return this;
                }

                public String getTargetResourceType() {
                        return myTargetResourceType;
                }

                public ResourceLinkForLocalReferenceParams setTargetResourceType(String theTargetResourceType) {
                        myTargetResourceType = theTargetResourceType;
                        return this;
                }

                public Long getTargetResourcePid() {
                        return myTargetResourcePid;
                }

                public ResourceLinkForLocalReferenceParams setTargetResourcePid(Long theTargetResourcePid) {
                        myTargetResourcePid = theTargetResourcePid;
                        return this;
                }

                public String getTargetResourceId() {
                        return myTargetResourceId;
                }

                public ResourceLinkForLocalReferenceParams setTargetResourceId(String theTargetResourceId) {
                        myTargetResourceId = theTargetResourceId;
                        return this;
                }

                public Date getUpdated() {
                        return myUpdated;
                }

                public ResourceLinkForLocalReferenceParams setUpdated(Date theUpdated) {
                        myUpdated = theUpdated;
                        return this;
                }

                public Long getTargetResourceVersion() {
                        return myTargetResourceVersion;
                }

                /**
                 * @param theTargetResourceVersion This should only be populated if the reference actually had a version
                 */
                public ResourceLinkForLocalReferenceParams setTargetResourceVersion(Long theTargetResourceVersion) {
                        myTargetResourceVersion = theTargetResourceVersion;
                        return this;
                }

                public PartitionablePartitionId getTargetResourcePartitionablePartitionId() {
                        return myTargetResourcePartitionablePartitionId;
                }

                public ResourceLinkForLocalReferenceParams setTargetResourcePartitionablePartitionId(
                                PartitionablePartitionId theTargetResourcePartitionablePartitionId) {
                        myTargetResourcePartitionablePartitionId = theTargetResourcePartitionablePartitionId;
                        return this;
                }
        }
}